Scalar i40 tapechanger LUN appearing as a second tape drive

[Dirk-Willem van Gulik]

> On 15 May 2018, at 22:19, Kenneth D. Merry <ken at FreeBSD.ORG> wrote:
> 
> On Sun, May 13, 2018 at 20:00:21 +0200, Dirk-Willem van Gulik wrote:
>> While having to re-surrect a Quantum Scalar i40 LTO5 unit - on a stock  11.1-RELEASE-p6  wired up with a external SAS cable to a HP Smart Array P222 I am seeing:
>> 
>> 	camcontrol devlist 
>> 	...
>> 	<HP Ultrium 5-SCSI Z6KZ>           at scbus3 target 4 lun 0 (sa0,pass1)
>> 	<HP Ultrium 5-SCSI Z6KZ>           at scbus3 target 4 lun 1 (pass2,sa1)
>> 	....	
>> 
>> rather than the tape drive on LUN 0 and the tape changer on LUN 1 (the control path is to this drive - the serial number matches - and in like with the web interface details). 
>> 
>> dmesg shows:
>> 
>> 	...
>> 	sa0 at ciss1 bus 32 scbus3 target 4 lun 0 
>> 	sa0: Serial Number C38CEFF000
>> 	...
>> 	sa1 at ciss1 bus 32 scbus3 target 4 lun 1
>> 	...
>> 	sa1: Serial Number C38CEFF000
>> 
>> The second drive (Serial C38CEFF004) is not wired up. Or if it is - it nicely shows up at the right (different) target and LUN0, without a second LUN.
>> 
>> Does this ring a bell with any one ? The kernel has ch(4), sa(4) and pass(4) compiled in statically (and is known to work with other tape changers/libraries).
>> 
> 
> When you hooked other tape changers up, was it to the same machine, and
> also to the ciss(4) controller?  Was the configuration the same?

Yes (but *).

> It looks like the array controller is moving things around.
> 
> I would suggest taking a look at configuration options for the controller
> to see if you can adjust the way it does passthrough.

The control-path can indeed be set. It is set correctly (we also tried the 3 other permutations possible).

> Or, if you can find one, put a standard SAS controller in there (as opposed
> to a RAID controller) and hook that up to the tape library.

Ok. good advice. Will do exactly that.

> It is unlikely that FreeBSD is causing this behavior.  It really looks like
> the RAID controller is giving you multiple copies of the same tape drive.

Thanks. The odd thing is that this very configuration/card/etc has worked around 8.x.

Dw

*: the Quantum Scalar i40’s have the annoying habit to self-check their firmware and prime themselves for auto update with a fairly easy to miss cancel prompt on the screen. So we are not a 100% it was not updated during the re-racking by someone going through the re-calibration mindlessly.